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Coinsurance and Copayment

Coinsurance

Co-insurance is an insurance-related term that describes a splitting or spreading of risk among multiple parties.

coinsurance
n : insurance issued jointly by two or more underwriters

Coinsurance \Co`in*sur"ance\, n. [Co- + insurance.]
Insurance jointly with another or others; specif., that
system of fire insurance in which the insurer is treated as
insuring himself to the extent of that part of the risk not
covered by his policy, so that any loss is apportioned
between him and the insurance company on the principle of
average, as in marine insurance or between other insurers.
[Webster 1913 Suppl.]